Photodiode device containing a capacitor for controlling dark current or leakage current

Abstract

An organic photodiode, including a first electrode forming an anode, an active layer, a second electrode, and at least one third electrode, forming a capacitance with another electrode, to trap at least part of dark current or leakage current.

The invention claimed is:   
     
       1. An organic photodiode, comprising:
 a first electrode forming an anode; 
 a second electrode forming a cathode; 
 an active layer provided between the first electrode and the second electrode; 
 at least one third electrode, the third electrode being provided in the active layer between the first electrode and the second electrode and being in contact neither with the first electrode nor with the second electrode, the third electrode forming with the first electrode or with the second electrode or with a fourth electrode distinct from the first and the second electrodes, plates of a capacitance to trap at least part of dark current or leakage current of the photodiode; and 
 means including tracks and/or pads enabling the third electrode and/or the fourth electrode to be powered using a voltage supply means, to apply a voltage across the capacitance, as a function of the dark current or the leakage current. 
 
     
     
       2. The device according to  claim 1 , further comprising a substrate on which the first electrode, the second electrode, and the third electrode are provided. 
     
     
       3. The device according to  claim 1 , further comprising a substrate on which the first electrode is provided, the second electrode being provided on the active layer. 
     
     
       4. The device according to  claim 3 , further comprising the fourth electrode provided in the active layer, between the first electrode and the second electrode, the fourth electrode forming, with the third electrode, the capacitance to trap part of the dark current or the leakage current. 
     
     
       5. The device according to  claim 1 , a material between plates of the capacitance being a material of the active layer. 
     
     
       6. The device according to  claim 1 , at least the third electrode being encapsulated in a portion of dielectric material. 
     
     
       7. The device according to  claim 6 , the dielectric constant of the dielectric material being higher than 2 and lower than 10. 
     
     
       8. The device according to  claim 6 , the dielectric material being polyvinyl phenol or polymethacrylate or polystyrene or silica or alumina. 
     
     
       9. The device according to  claim 1 , the active layer being a mixture of n and p-type layer.